WARNING in __ioremap_caller

Status: upstream: reported C repro on 2026/02/22 11:33
Subsystems: kernel
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+49b1021becba70c1f3f6@syzkaller.appspotmail.com
Fix commit: 4590752e20aa mm: disallow ioremap'ing ordinary RAM in generic_access_phys()
Patched on: [ci-qemu-gce-upstream-auto ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci-upstream-rust-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu-native-arm64-kvm ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root]
First crash: 264d, last: 1d09h
▶ ▼ ✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision
e5ec6b42 repro-c Reproduced: ✅ ❓ WARNING in __ioremap_caller 2026/08/06 20:23 2026/08/07 10:10 2026/08/07 13:32 c38879ea
d1ea2ef5 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ✅ ❓ WARNING in __ioremap_caller 2026/05/26 05:01 2026/05/26 05:01 2026/05/26 05:58 c69befb3
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
[PATCH] mm: disallow ioremap'ing ordinary RAM in generic_access_phys() 4 (4) 2026/10/14 15:53
[PATCH] mm: don't ioremap COWed anon pages in generic_access_phys() 11 (11) 2026/10/13 07:20
[syzbot] [kernel?] WARNING in __ioremap_caller 1 (3) 2026/09/04 23:20
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 WARNING in __ioremap_caller -1 syz, C 28 10d 32d 0/2 upstream: reported C repro on 2026/10/09 00:05
linux-6.1 WARNING in __ioremap_caller origin:upstream -1 syz, C 27 7d21h 32d 0/3 upstream: reported C repro on 2026/10/09 01:35
linux-5.15 WARNING in __ioremap_caller -1 syz, C 25 9d06h 32d 0/3 upstream: reported C repro on 2026/10/08 22:47
android-6-12 WARNING in __ioremap_caller origin:upstream -1 syz, C 2 29d 64d 0/1 premoderation: reported C repro on 2026/09/06 17:28
▶ ▼ Last patch testing requests (1)
Created Duration User Patch Repo Result
2026/09/26 23:08 13m retest repro upstream report job log log

Sample crash report:
ioremap: invalid physical address 8000000000000000
------------[ cut here ]------------
1
WARNING: arch/x86/mm/ioremap.c:206 at __ioremap_caller+0x51e/0x620 arch/x86/mm/ioremap.c:206, CPU#0: syz-executor409/5603
Modules linked in:
CPU: 0 UID: 0 PID: 5603 Comm: syz-executor409 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:__ioremap_caller+0x51e/0x620 arch/x86/mm/ioremap.c:206
Code: 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 e4 7f 4d 00 48 8b 74 24 60 48 c7 c7 a0 0b 6a 8b e8 e3 0d ae ff 90 <0f> 0b 90 e9 49 fd ff ff 4c 8b 74 24 28 41 81 e6 ff 0f 00 00 4d 01
RSP: 0018:ffffc90004c4f880 EFLAGS: 00010246
RAX: 0000000000000032 RBX: 1ffff92000989f00 RCX: 5b95166a22756f00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004c4f990 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000989ec1 R12: 0000000000020000
R13: 000000000000002e R14: 8000000000000fff R15: dffffc0000000000
FS:  0000555562d39400(0000) GS:ffff8881249bb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005583c296b000 CR3: 000000002a3d8000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 phram_map drivers/mtd/devices/phram.c:92 [inline]
 register_device+0x12c/0x570 drivers/mtd/devices/phram.c:139
 phram_setup+0x412/0x620 drivers/mtd/devices/phram.c:324
 param_attr_store+0x214/0x310 kernel/params.c:591
 module_attr_store+0x65/0x90 kernel/params.c:906
 kernfs_fop_write_iter+0x3a5/0x540 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x61e/0xbb0 fs/read_write.c:687
 ksys_write+0x156/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffa7d609549
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 d8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe9a9166e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000200000000100 RCX: 00007ffa7d609549
RDX: 000000000000001d RSI: 0000200000000200 RDI: 0000000000000003
RBP: 0000000000000001 R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000006 R11: 0000000000000246 R12: 00007ffe9a916858
R13: 0000200000000104 R14: 00007ffa7d69cc40 R15: 0000000000000002
 </TASK>

Crashes (635):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/14 16:21 upstream 4056b3c9d3c9 1a71827b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in __ioremap_caller
2026/10/29 15:35 upstream c339f4010dea 4902417d .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/09/12 22:57 upstream 5225b8eec4c9 70a60e12 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/07 16:13 upstream d48723711bae 5cecaf1f .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/09/04 22:02 upstream bc35965f6940 44dda43b .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/07 13:43 upstream d48723711bae 5cecaf1f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/11/06 05:33 upstream d68ce4e71248 5cecaf1f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/11/03 23:36 upstream 05441d697f7f d02c3949 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/11/03 21:31 upstream 05441d697f7f d02c3949 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __ioremap_caller
2026/11/03 21:30 upstream 05441d697f7f d02c3949 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __ioremap_caller
2026/11/02 06:48 upstream 46fec1c3029b 25a0ae84 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/11/02 05:33 upstream 46fec1c3029b 25a0ae84 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in __ioremap_caller
2026/11/01 10:03 upstream cbbddb6b08cc 25a0ae84 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/10/31 22:48 upstream 36aad21d50d1 2041d3f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/10/31 22:20 upstream 36aad21d50d1 2041d3f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in __ioremap_caller
2026/10/31 19:40 upstream 36aad21d50d1 2041d3f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/10/31 18:30 upstream 36aad21d50d1 2041d3f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/10/31 16:27 upstream 36aad21d50d1 2041d3f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __ioremap_caller
2026/10/31 15:25 upstream 36aad21d50d1 2041d3f8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in __ioremap_caller
2026/10/30 23:39 upstream d89e1d186ec9 0ec395f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in __ioremap_caller
2026/10/30 21:47 upstream d89e1d186ec9 0ec395f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in __ioremap_caller
2026/10/28 15:46 upstream 65ba8f34ec88 858db2ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in __ioremap_caller
2026/07/15 16:51 upstream 58717b2a1365 a4ed0f4f .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in __ioremap_caller
2026/07/02 12:56 upstream 4a50a141f05a 27192279 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in __ioremap_caller
2026/04/14 18:23 upstream d60bc1401583 362d1323 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in __ioremap_caller
2026/02/18 11:27 upstream 2961f841b025 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in __ioremap_caller
2026/11/04 09:06 upstream 05441d697f7f 5af5b6c6 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/04 05:58 upstream 05441d697f7f 5af5b6c6 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/03 13:32 upstream 6628e7d4c6b2 e2d35131 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/03 08:19 upstream 6628e7d4c6b2 0a94d799 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/03 05:06 upstream 6628e7d4c6b2 0a94d799 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/02 20:57 upstream 6628e7d4c6b2 6969b601 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/02 17:57 upstream 6628e7d4c6b2 6969b601 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/02 16:05 upstream 6628e7d4c6b2 6969b601 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/02 13:21 upstream 6628e7d4c6b2 6969b601 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/02 07:58 upstream 46fec1c3029b 25a0ae84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/02 03:52 upstream 46fec1c3029b 25a0ae84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/02 02:37 upstream 46fec1c3029b 25a0ae84 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __ioremap_caller
2026/11/01 23:09 upstream 46fec1c3029b 25a0ae84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/01 21:39 upstream 46fec1c3029b 25a0ae84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/01 12:56 upstream cbbddb6b08cc 25a0ae84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/10/31 13:37 upstream 36aad21d50d1 2041d3f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/10/31 11:23 upstream abf8c33470f7 2041d3f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/10/31 08:21 upstream abf8c33470f7 2041d3f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/10/31 07:17 upstream abf8c33470f7 2041d3f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/10/31 06:15 upstream abf8c33470f7 2041d3f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/10/31 02:06 upstream abf8c33470f7 2041d3f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/10/31 00:52 upstream abf8c33470f7 2041d3f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/10/31 00:41 upstream abf8c33470f7 2041d3f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __ioremap_caller
2026/11/08 19:44 upstream fa4ad798f6f6 5cecaf1f .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/07 09:55 upstream d48723711bae 5cecaf1f .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/07 00:29 upstream f66469d9905b 5cecaf1f .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/06 06:59 upstream d68ce4e71248 5cecaf1f .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/03 01:44 upstream 6628e7d4c6b2 0a94d799 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/02 15:01 upstream 6628e7d4c6b2 6969b601 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/01 20:23 upstream cbbddb6b08cc 25a0ae84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/01 18:58 upstream cbbddb6b08cc 25a0ae84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/11/01 17:12 upstream cbbddb6b08cc 25a0ae84 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __ioremap_caller
2026/10/31 12:39 linux-next 7649ba73f9e7 2041d3f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __ioremap_caller
2026/10/31 09:41 linux-next 7649ba73f9e7 0ec395f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __ioremap_caller
2026/10/31 05:03 linux-next 7649ba73f9e7 0ec395f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __ioremap_caller
2026/10/31 03:43 linux-next 7649ba73f9e7 0ec395f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in __ioremap_caller
2026/10/30 23:28 linux-next 7649ba73f9e7 0ec395f8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __ioremap_caller
* Struck through repros no longer work on HEAD.